document.write( "Question 217304: Kindly answer this question please!!! Thanks!!!! A commander pilot and an assistant for a flight to Mars are chosen from 15 astronauts. In how many ways can the two men be chosen for the 2 positions? \n" ); document.write( "

Algebra.Com's Answer #163911 by Theo(13342) $\"\"$ $\"About$

You can put this solution on YOUR website!
The answer is $\"%2815%21%29+%2F+%28%282%21%29%2A%2813%21%29%29+=+%2815%2A14%29%2F%281%2A2%29+=+105\"$
\n" ); document.write( "-----
\n" ); document.write( "To make it easier to show, assume it was 5 candidates for 2 positions.
\n" ); document.write( "The formula would then be $\"%285%21%29+%2F+%28%282%21%29%2A%283%21%29%29+=+%285%2A4%29%2F%282%2A1%29+=+10\"$
\n" ); document.write( "Let the 5 candidates be abcde
\n" ); document.write( "Then the possible ways they could be chosen would be:
\n" ); document.write( "ab
\n" ); document.write( "ac
\n" ); document.write( "ad
\n" ); document.write( "ae
\n" ); document.write( "bc
\n" ); document.write( "bd
\n" ); document.write( "be
\n" ); document.write( "cd
\n" ); document.write( "ce
\n" ); document.write( "de
\n" ); document.write( "-----
\n" ); document.write( "Same concept applies with larger numbers.
\n" ); document.write( "Your answer is 105 different ways.
\n" ); document.write( "-----
\n" ); document.write( "The general formula for x positions chosen out of n candidates is:
\n" ); document.write( " $\"%28n%21%29%2F%28%28n-x%29%21%2A%28x%29%21%29\"$
\n" ); document.write( "-----
\n" ); document.write( " \n" ); document.write( "

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